A number of proposals today support a substantial increase in foreign aid levels to sub-Saharan Africa even though this region already receives a historically unprecedented volume of aid. This essay reviews the evidence regarding the potentially negative effects of aid dependence on state institutions, a topic which has received relatively little attention. We note several pathways through which political institutions might be adversely affected and devote particular attention to fiscal and state revenue issues. In addition to reviewing the economic literature on the aid-revenue relationship, this essay brings in the longstanding political science literature on state-building to consider the potential impact of aid dependence on the relationship between state and citizen. We conclude that states which can raise a substantial proportion of their revenues from the international community are less accountable to their citizens and under less pressure to maintain popular legitimacy. They are therefore less likely to have the incentives to cultivate and invest in effective public institutions. As a result, substantial increases in aid inflows over a sustained period could have a harmful effect on institutional development in sub-Saharan Africa.